Pressure-gage.



c. 0. EVERHART. PRESSURE GAGE.

APPLIGA TION FILED JULY 3, 1911.

1,022,310. Patented Apr. 2, 1912.

// by I: Aug/f .4 TTORNEIIS INVENTOR.

UNITED.. STATES PATE troF IcE? ensures o.: -'evmanr; or WARREN, mas-marsh; ntend err-murmur; r

AQUILLA.M-ILES ,'-ZOF WARREN, I'ENNSXLVA To. whom it may concern:

- Be' a kaow art I, CHARLES 'o.- EVER.

-1- A1 z r,. a'- citizen of. the-United States, residl at 'W'arren, in the county of lVarren '5' 1 and tate of Pennsylvania, have invented certain new-and useful Improvements in Pressure-Gages; and Ida declare the following to be a full, clear; and exact description' of the-invention, such as" will enable -1 0 skilled in the art to which it ap- V pertains to make and use the same.

invention relates to measuring in "strume' nts, more-es cially to' pressure ges; and the object. o the same is to pro-v 'V vwhi'ch'will 'be sounded. when the" pressure e'r'agage of-jthis kind. with an alarm reaches either ahigh or low extreme, within certain-ilimits'which. maybe determined by 6et ting --.-the mechanism, and yet of such character that therewill be no interruption "to'y'the' continued movement of the hand- 1 above or. below thepoints where th'e sound 'ings'oft'the alarm commences atcither extreme.

The objectsof this invention are carried ;out by the construction hereinafter more full describedaud claimed, and as shown .-int e drawings. whrein- Figure 1 is a,pla-n view. of this improved 80' gagewith the faceplate removed so as to show the internal mechanism; Fig. 2 is a section on-the line 2-2 of Fig. 1.

:1n the drawings the letter C designates the casing whereon is inscribed or may be 85 supported a. dial D havin a scale on its face rover which mov'es the t p of the hand H which is centrally pivoted in the casing and restored toits normal position at zero on the dial by means of a air'spring H. On

the 'arbor of this dial is a pinion P meshing with a toothed sector S which is pix-' oted at a in an arm A and'whose outer end is connected by a link L with an expansive element E which is'usually a piece of copper tubing.

The letter I designates an inlet valve by means of which the fluid ressure is admit ted to the interior of-t e'e'xpansive element, and the constructionw hich is usual in gages of this character-is such that;

when the pressure increases the, expansive element E straightens out slightly so that the link L draws onthetoothed segment and:

, reassure-GAG NIA. 3

v w ess w era enae epea-raie. Aplll cationfiledJuly a, wul s riai No. 636,572. #151 the t eeth thereon intermeshing wi tli pinion P cause the hand to turn over thescalc on 55 the dial.

Coming now more particularly to the present invention, the numeral 1 designates an insulated plug passing through the' cas ing C, and through this plugare led the two so wires 2 and 3 of .a CII'CUIiZ which passes through a bell 1 or other signal anda battery 5, the inner endof one wire 2 being connected with the casing C,"and the inner end' of the' other wire being braced as at 5 6 and led to two contact points whose"specific construction forms thegist of the present invention. i

-Referring'nowparticularly to Fig. 2', each point comprises a metallic terminal 10 -having'a longitudinal slot 11 in its body which engages loosely-beneath the head of a screw 12- which is'seated in an insulatingblock 'l3'mounted'suitably within the casing C; and the outer'end of this terminal is turned up into an car 14 in which is swive'led the head l5. ofa screw 16 which is threaded through an insulating nut .17 mounted .in the casing 0 andwhose 'thumbpiece 18 stands on the exterior thereof. The' cons0 struction is such that by manipulating this screw through thumb piece 18 its shank may be adjustedin or out through the nut 17 and its swiveledhead 15 which loosely engages the ear l i will-cause the slotted terminal plate 10 to move longitudinallyover the screw 12 and upon the surface of the insulating block 13. The inner extremity of said plate 1O is twisted and formed into a finely tempered contact spring 20 (or this spring may be a separate member attached to the plate 10) whose position is such that when the toothed sector swings'to a proper degree its edge will make contact with the extremity of this spring but the latter will yield easily when the sector swings farther in the same direction. As shown in Fig. 2, there are two of these terminals, each independently adjustable by means of its set screw, and they are directed inward on substantially radial lines toward the CGIIiGI Of' the casing and stand at opposite sides of the sector S and sutficiently remote therefrom to permit itto have all the usual movements a; and fro without coming in contact with either of the springs Q0. Yet the flaring shape of the sector S is such thatwhen these terminals are adjusted inward their springs approach nearer and nearer to the edges of said sector and the possible field of movement of the latter is restricted; and the ad justment of the terminals in the opposite direction amplifies its field of movement as will be clear.

The use of this device as a pressure gage is that which such instruments ordinarily have, and obviously it canjbo employed to I I pivoted ll] the casing, and an expansible clemeasure the pressure ot any tluid desired.

The setting oi the adjustable terminals will be clear from the above description. When the pressure swings the sector in either direction, a Circuit is closed from the battery through the bell or other alarm. the wire 2, casing C, pivot a, and sector S; to the tip of one spring 20 and thence along its terminal plate 10 to the branch wire 6 and by the other wire 3 back to the battery. Hence it'will be seen that the device may be set tosound an alarm whenever the pressure reaches any desired extreme, either high or low; but the contact springs 20 are so light and flexible that when the sector touches them and the alarm commences, its further movement is not impeded to any appreciable extent. I consider it advisable and advantageous to have the terminals 10 adjustable radially inward (or practically so) rather than on lines substantially at right angles to the length of the Strn'iIOl, because the construction illustrated and described permits an extremely fine adjustment of such terminals without necessitating the use, of

screws whose threads are so fine that they would be ditlicult to manufacture.

The parts are obviously cf the desired ma; terials and proportions and considerable change in details may be made without departingfrom the principle of my invention.-

lVhat is claimed as new is: a

Ina pressui'e gage, the cmnbilP-timt with the casing having a dial, a hand moving t'hereover and having a pinion on its arbor. a toothed sector engaging said pinion an ment contrt'llling the movement ol said sector; of an insulating block within the casing, screws therein at either side 0t said sector, two adjustable terminals, each comprising a body having a longitudinal slot loosely engaging one of said screws, an upturned ear at its outer end,and a contact springat its inner end standing in the path of said sector, insulating nuts carried by said casing set screws engaging said nuts and having heads at their inner ends swiveled in said ears, said screws and terminals being directed substantially inward toward the center of the casing, and an alarm circuit whereof one terminal is connected with both said terminals and the other with the sector.

In testimony whereof I have hereunto set my hand iii-presence of two subscribing witnesses.

CHAR-LES O. EVEltlIAlt'l.

Witnesses:

AQUILLA Mines; J OHN Konnnnr.

t l t l a t i t t 

